that's a key distinction in law enforcement technology but it means among the leads being followed, leads to the questioning of that individual. he's at a hospital, we are told, a heavily police guarded hospital. other information, two dead, two confirmed dead as we know, one of them an 8-year-old boy. 132 to 140 of those injured, as that information comes in. you're in the city of boston so you see what happens after an event like this. upgraded screenings at logan airport and other airports in the area. again, i'm told not looking for any one or any specific group of individuals, just routine upgrading, racheting up of security. also just got word that u.s. coast guard is now increasing patrols in the boston harbor area. again, one of the questions in a situation like this is, is this an isolated attack, isolated episode in the heart of boston or is it part of a plot that would lead to follow-on attacks either in boston or elsewhere. that is among the many questions, many questions investigators are trying to answer tonight. >> i can tell you, you hear some police vehicles going by us r